Sample Question #213 (brainteaser)
What’s the first time after 3 o’clock that the hour and minute hands on a clock face overlap each other?
This kind of clock hands question is very popular, and easy to solve.
We know that every hour the hour hand moves 360/12=30 degrees around the clock face. Since there are 60 minutes in an hour, this means the hour hand moves 30/60=0.5 degrees per minute. The minute hand moves 360/60=6 degrees per minute. Therefore, let x be the target time in minutes, for this question we have (since at 3 o’clock the hour hand is at 90 degrees)
90 + x/2 = 6x ==> x = 16.36
So the time would be 3:16:22.
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